Allied Telesis 6870 manual Checking The Liquid Nitrogen Level

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6.4 Checking The Liquid Nitrogen Level

Every time you remove or insert a vial, note the level of liquid nitrogen (LN) in the tub. You should top off the LN when needed as a matter of routine. If your programmed grinding cycle includes more than twenty or thirty minutes of actual grinding time, you should visually check the nitrogen level at about that point and add more if needed. We do not recommend cumulative grinding time of more than thirty minutes per run, as after that much grinding the LN level is close to the point where the LN sensor will shut down the mill. However, if you must run the mill for an extended time, and the LN sensor stops the grinding program, the mill can be refilled with LN and the grinding program resumed where it stopped.

The 6870 Freezer/Mill can be refilled automatically with the 6820 Auto-Fill System, which adds LN to the tub when the LN level is low. The 6820 Auto-Fill System must be installed and calibrated at our factory, so if you did not order your 6870 Freezer/Mill with an Auto-Fill System and want to order one later, the Freezer/Mill must be returned to SPEX SamplePrep LLC for installation and calibration.

6.5 6820 Auto-Fill System: Description, Installation, Operation

Description: the 6820 Auto-Fill System automatically transfers liquid nitrogen (LN) to the 6870 Freezer/Mill during operation, making hand-filling unnecessary. The Auto-Fill mechanism includes a cryogenic valve linked to LN sensors in the tub. When the LN level is low, the valve opens during Pre-Cool or Re-Cool stages to let LN into the tub. The Auto-Fill System as supplied also includes a safety valve for the LN transfer hose.

LN transfer hoses can vary with the LN supply tank or line, so one is not included with the 6820 Auto-Fill System. Four-foot and six-foot transfer hoses of standard design (part numbers 6906 and 6907) can be purchased from SPEX SamplePrep, or custom transfer hoses can be designed and supplied by the user. The LN inlet is a male ½ inch JIC fitting placed low on the right side of the Freezer/Mill, so the outlet of the hose requires a female CGA295 fitting. The 160 liter and 240 liter LN tanks used by many of our customers generally have a male 3/8” (9.5 mm) NPT outlet, so SPEX transfer hoses come with a matching female 3/8 in. NPT fitting. We do not recommend excessively long transfer hoses.

LN tanks come in two types, high-pressure and low-pressure. Some LN tanks have valve systems to switch from low pressure to high pressure. Always use a low-pressure LN supply,

with maximum pressure of about 20 psi.

Installation: install the safety valve on the outlet of the tank or LN line, with the gooseneck tilted up and the valve outlet down. Then attach the LN transfer hose to the safety valve, and the other end to the inlet on the Freezer/Mill. The safety valve should be higher than the LN inlet on the Freezer/Mill. The purpose of the safety valve is to have an outlet for nitrogen vapor in case the mill and supply tank valves are both shut, and pressure builds up inside the hose.

When installing the safety valve and transfer hose, use Teflon plumber’s tape on all joints, and tighten the nuts with a wrench. If the joints leak, tighten them further and/or use more tape.

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SPEX SamplePrep LLC

9.24.07

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Contents FREEZER/MILL This manual is part numberTable of Contents Safety Notes Introduction6870 FREEZER/MILL Specifications Safety FeaturesType of mill cryogenic impact mill Typical Sample CapacityUnpacking Electrical Hookup Setting UPPower Switch and Control Panel Lid and Lid Latch, Coil Assembly and Coil Gate, LN Sensor Grinding Vial Sizes, Adapters, and Vial Openers Logo Screen Current Settings ScreenTouchscreen Displays Rate Status ScreenStatus Screen during a run Settings Screen Settings ScreenSTORE/RECALL Screens Storing a new programAdding Liquid Nitrogen Coolant Recalling a programPractical Operation Section Putting a Cold Sample into the Vial and Keeping it Cold Putting a Sample into the Vial at Room TemperatureSize of Sample Pieces Putting a Very Small Sample in the Vial and Keeping it Cold Placing Vials in the Freezer/Mill CoilOpening the Vials Emptying the VialsCleaning the Vials 6820 Auto-Fill System Description, Installation, Operation Checking The Liquid Nitrogen LevelMaintenance Warranty and Service WarrantyProduct Specifications To Arrange a Return ShipmentDalston Gardens Stanmore, HA7 1BQ Great Britain Contacting Spex SamplePrep LLCSpex SamplePrep LLC Liberty St Metuchen, New Jersey TROUBLE-SHOOTING GUIDE, page 1 Problem Cause SolutionTROUBLE-SHOOTING GUIDE, page 2

6870 specifications

The Allied Telesis 6870 is a robust Layer 3 Ethernet switch designed for high-performance networking in enterprise environments. Incorporating advanced features and technologies, it serves as a vital component in managing complex network infrastructures, ensuring seamless connectivity, reliability, and enhanced performance.

One of the standout characteristics of the 6870 is its support for a high number of Gigabit Ethernet ports. With multiple SFP and SFP+ ports, the switch allows for flexibility in connecting various devices, while also facilitating the use of different physical media. This capability is crucial for organizations that demand versatile connection options, particularly when managing diverse networking equipment.

The switch is equipped with advanced Layer 3 routing capabilities, allowing it to perform IP routing functions in addition to standard Ethernet switching. Suitable for traffic management, the switch supports protocols such as OSPF, RIP, and static routing, enabling efficient and intelligent path selection in larger networks. This functionality is essential for optimizing bandwidth usage and maintaining an efficient data flow throughout the network.

Another highlight of the Allied Telesis 6870 is its support for VLANs (Virtual Local Area Networks). VLANs enable network segmentation, improving security and performance by isolating different segments of traffic. This capability is further enhanced by the switch's support for advanced features like Ingress/Egress Rate Limiting and Quality of Service (QoS). These features allow network administrators to prioritize critical applications and ensure that bandwidth is allocated effectively.

The switch also incorporates the innovative Allied Telesis Autonomous Management Framework (AMF), which simplifies device management and network configuration. With AMF, administrators can manage multiple switches as a single logical entity, reducing operational complexity and minimizing downtime. This technology supports zero-touch provisioning, enabling rapid deployment and configuration of network devices.

Security is another key aspect of the 6870, with features such as Access Control Lists (ACLs) and IEEE 802.1X port-based authentication. These measures help protect the network from unauthorized access and ensure that only authenticated devices can connect to the network.

In summary, the Allied Telesis 6870 is a versatile and powerful switch that meets the demands of modern enterprise networks. With its comprehensive feature set, including high-performance routing, VLAN support, and advanced management capabilities, it offers a reliable solution for organizations seeking to optimize their network infrastructure. Whether for deploying new services or managing existing traffic, the 6870 stands out as a formidable choice for network administrators.
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